For purposes of this invention a pleated shade shall be defined as a shade, blind, screen, curtain, or other similar member for covering an opening which, when in its opened condition to expose the opening, stacks generally along predetermined creases or lines. Pleated shades are generally formed from a web-type material which retains its folds, for example impregnated textile fabric, paper or board type material, metalized textile material, etc. Other materials may also be used such as plastics and metals. Such shades are for example shown in Dutch Patent 167,220 and in U.S. Pat. No. 3,946,788 entitled "Foldable Curtain Screen or Blind Construction and a Method for Producing a Curtain Blind Construction" issued Mar. 30, 1976, to Hendrik van Muyen. Other forms of pleated shades include, but are not limited to, the various honeycomb and other shade configurations shown in co-pending application Ser. No. 030167 entitled "Shade and Method For the Manufacture Thereof", filed Mar. 25, 1987, and romans-style shades. In such shades, the material is attached between a horizontal headrail and a horizontal bottomrail, and the bottomrail is moved up and down under control of cords to uncover or cover the opening. Such a configuration is thus suitable only for covering a substantially rectangular opening and is not suitable for covering openings having triangular or other non-rectangular shapes. Since architects frequently design windows having non-rectangular shapes either to achieve a desired aesthetic effect or because of structural or functional limitations, a need exists for a pleated shade construction which can be used to cover such non-rectangular openings.